Theriva™ Biologics Reports Full-Year 2023 Operational Highlights and Financial Results

– The independent data monitoring committee (IDMC) recommended the continuation of VIRAGE, the Phase 2b clinical trial of VCN-01 in combination with chemotherapy for metastatic Pancreatic Ductal Adenocarcinoma (PDAC), with no safety concerns raised -

- VIRAGE remains on track to complete enrollment in the first half of 2024-

- As of December 31, 2023, Theriva Biologics reports $23.2 million in cash, which is expected to provide runway into the first quarter of 2025 -

- Conference call and webcast to be held on Monday, March 25 at 8:30 a.m. ET -

ROCKVILLE, Md., March 25, 2024 (GLOBE NEWSWIRE) -- Theriva™ Biologics (NYSE American: TOVX), a diversified clinical-stage company developing therapeutics designed to treat cancer and related diseases in areas of high unmet need, today reported financial results for the full-year ended December 31, 2023, and provided a corporate update.

“With continued advancement of our clinical programs, we have the opportunity to achieve several important milestones this year,” said Steven A. Shallcross, Chief Executive Officer of Theriva Biologics. “VIRAGE, our Phase 2b trial of VCN-01 in newly-diagnosed metastatic PDAC remains on track to complete enrollment in the first half of 2024. We completed the first safety review with the IDMC, and with a positive recommendation, VIRAGE will continue to enroll patients as planned with no modifications to the protocol. Our clinical data has demonstrated that repeated systemic dosing of VCN-01 is feasible from a safety perspective, and will now focus on determining whether the repeated-dose regimen of VCN-01 may lead to improved clinical outcomes for patients with PDAC and other solid cancers. In addition to advancing the VIRAGE PDAC trial, we continue to work closely with key opinion leaders, and regulatory agencies to refine our protocol and clinical strategy for VCN-01 as an adjunct to chemotherapy in pediatric patients with advanced retinoblastoma. In parallel, our investigator sponsored Phase 1 trial evaluating the safety and activity of intravitreal VCN-01 in pediatric patients with refractory retinoblastoma continues to progress and will further inform our clinical development pathway in this area of high unmet need.”

Recent Program Highlights and Anticipated Milestones:

VCN-01:

• Pancreatic Ductal Adenocarcinoma (PDAC): Dosing is underway and enrollment continues to progress for VIRAGE, the randomized, controlled, multicenter, open-label Phase 2b trial of VCN-01 in combination with standard-of-care chemotherapy (gemcitabine/nab-paclitaxel) as a first line therapy in newly diagnosed bmetastatic PDAC patients. The trial is expected to enroll 92 evaluable patients and remains on track to complete enrollment in H1 2024.
• The Independent Data Monitoring Committee (IDMC) recommended the continuation of enrollment as planned into the VIRAGE study. According to the IDMC's expert assessment of clinical data from patients enrolled at six sites open in the U.S. and nine sites in Spain, the ongoing Phase 2b trial will continue without any changes to the protocol. No safety concerns were raised based on the evaluation of data presented at the IDMC meeting. Intravenous VCN-01 has been well tolerated and demonstrated a safety profile consistent with prior clinical trials. Importantly, no additional toxicities were observed in patients receiving a second dose of VCN-01.
• Retinoblastoma: The investigator sponsored Phase 1 trial evaluating the safety and activity of intravitreal VCN-01 in pediatric patients with refractory retinoblastoma has completed patient treatment. The trial is designed to evaluate escalating doses of VCN-01 administered by two intravitreal injections separated by 14 days. The investigator sponsored Phase 1 trial, which will complete patient follow-up in H1 2024, will help inform the planned Phase 2 trial design.
• This builds on positive preclinical results presented by collaborators at Fundació Sant Joan de Déu demonstrating that administration of VCN-01 in combination with topotecan chemotherapy may improve VCN-01 activity against retinoblastoma.

SYN-004 (ribaxamase):

• Dosing is underway for the ongoing Phase 1b/2a randomized, double-blinded, placebo-controlled clinical trial of SYN-004 (ribaxamase) in allogeneic hematopoietic cell transplant (HCT) recipients for the prevention of acute graft-versus-host-disease (aGVHD). SYN-004 appeared to be well tolerated in HCT patients treated with IV meropenem and SYN-004 was not detected in blood samples from the majority of the evaluable patients. The trial is on track to complete enrollment into the second cohort in Q2 2024.

Business Updates

• On November 2, 2023, Theriva signed an exclusive option to license intellectual property from Sant Joan de Déu-Barcelona Children’s Hospital (SJD) to explore the therapeutic potential of VCN-01 in combination with topoisomerase I inhibitors. This strengthens a long-term research collaboration with SJD and builds on ongoing trial evaluating VCN-01 in pediatric cancers.
• Theriva is actively pursuing licensing discussions for our SYN-020 intestinal alkaline phosphatase asset.

Full-Year Ended December 31, 2023 Financial Results

General and administrative expenses decreased to $7.1 million for the year ended December 31, 2023, from $9.9 million for the year ended December 31, 2022. This decrease of 28% is primarily comprised of the decrease in the fair value of the contingent consideration of $2.8 million, along with lower salary, investor relations, legal costs, consulting fees related to the VCN acquisition, and director and officer insurance offset by higher audit fees, and other consulting fees. The charge relating to stock based compensation expense was $0.4 million for the year ended December 31, 2023, compared to $0.4 million for the year ended December 31, 2022.

Research and development expenses increased to $14.3 million for the year ended December 31, 2023, from $11.7 million for the year ended December 31, 2022. This increase of 22% is primarily the result of higher clinical trial expenses related to our VIRAGE Phase 2 clinical trial of VCN-01 in PDAC, offset by lower expenses related to our Phase 1b/2a clinical trial of SYN-004 (ribaxamase) in allogeneic HCT recipients, the completed Phase 1a clinical trial of SYN-020, decreased manufacturing expenses related to our Phase 1a clinical trial of SYN-020 and lower other indirect costs. We anticipate research and development expense to increase as we continue enrollment in our VIRAGE Phase 2 clinical trial of VCN-01 in PDAC and our ongoing Phase 1 clinical trial in retinoblastoma, expand GMP manufacturing activities for VCN-01, and continue supporting our VCN-11 and other preclinical and discovery initiatives. Research and development expenses also include a charge relating to non-cash stock-based compensation expense of $165,000 for the year ended December 31, 2023, compared to $112,000 for the year ended December 31, 2022. In addition, we expect research and development expenses to increase as we incur higher clinical program costs for our VCN product candidates.

Other income was $1,442,000 for the year ended December 31, 2023, compared to other income of $471,000 for the year ended December 31, 2022. Other income for the year ended December 31, 2023 is primarily comprised of interest income of $1,439,000 and an exchange gain of $3,000. Other income for the year ended December 31, 2022 is primarily comprised of interest income of $512,000 offset by an exchange loss of $41,000.

Cash and cash equivalents totaled $23.2 million as of December 31, 2023, compared to $41.8 million as of December 31, 2022.

The audited financial statements for the year ended December 31, 2023 included in the Company’s Annual Report on Form 10-K contain an unqualified audit opinion from the Company’s independent registered public accounting firm that includes an explanatory paragraph related to the Company's ability to continue as a going concern.

Conference Call

Theriva Biologics will host a conference call on Monday, March 25, 2024 at 8:30 a.m. ET to discuss its financial results for the full-year ended December 31, 2023 and provide a corporate update. Individuals may participate in the live call via telephone by dialing 1-877-451-6152 (domestic) or 1-201-389-0879 (international) and using the conference ID: 13744453. Participants are asked to dial in 15 minutes before the start of the call to register. Investors and the public can access the live and archived webcast of this call via the “News & Media” section of the company’s website, https://www.therivabio.com, under “Events” or by clicking here, up to 90 days after the call.

About Theriva™ Biologics, Inc.

Theriva™ Biologics (NYSE American: TOVX), is a diversified clinical-stage company developing therapeutics designed to treat cancer and related diseases in areas of high unmet need. The Company is advancing a new oncolytic adenovirus platform designed for intravenous (IV), intravitreal and antitumoral delivery to trigger tumor cell death, improve access of co-administered cancer therapies to the tumor, and promote a robust and sustained anti-tumor response by the patient’s immune system. The Company’s lead candidates are: (1) VCN-01, an oncolytic adenovirus designed to replicate selectively and aggressively within tumor cells, and to degrade the tumor stroma barrier that serves as a significant physical and immunosuppressive barrier to cancer treatment; (2) SYN-004 (ribaxamase) which is designed to degrade certain commonly used IV beta-lactam antibiotics within the gastrointestinal (GI) tract to prevent microbiome damage, thereby limiting overgrowth of pathogenic organisms such as VRE (vancomycin resistant Enterococci) and reducing the incidence and severity of acute graft-versus-host-disease (aGVHD) in allogeneic hematopoietic cell transplant (HCT) recipients; and (3) SYN-020, a recombinant oral formulation of the enzyme intestinal alkaline phosphatase (IAP) produced under cGMP conditions and intended to treat both local GI and systemic diseases. For more information, please visit Theriva Biologics’ website at www.therivabio.com.